Physicochemical properties of a high molecular weight levan from Brenneria sp EniD312

A high molecular weight levan was produced by a novel levansucrase and some properties of this polymer were investigated. The levan exhibited a poroid microstructure as well as series of individual ellipsoidal or spheroidal particles. The weight-average molecular weight (M-w) of the levan was determined to be 1.41 x 10(8) Da. In a 0.1% solution, the levan showed a mean diameter of 176 nm, while in a 1% solution the diameter was 182 nm. The decomposition temperature was determined to be 216.67 degrees C, with an endothermic peak at 147.41 degrees C and a melting enthalpy of 76.9 J/g, The small angle X-ray diffraction pattern showed a distinctive peak pattern between 15 degrees and 40 degrees (2q). The levan solution showed a shear-thinning behaviour. These results suggest this levan could be a good additive in the food processing industry, as well as an important bio-based material in the medicinal or chemical industry. (C) 2017 Elsevier B.V. All rights reserved.